This standard specifies the determination method of iron content in SmCo 1-5 permanent magnet alloy powder. This standard is applicable to the determination of iron content in SmCo 1-5 permanent magnet alloy powder, the determination range is: 0.02% ~ 0.50%. GB/T 15679.2-1995 Chemical analysis method of SmCo permanent magnet alloy powder Determination of iron content GB/T15679.2-1995 Standard download decompression password: www.bzxz.net

National Standard of the People's Republic of China
Chemical analysis method of cobalt permanent magnet alloy powder
Determination of iron content
Samarium cobalt permanent magnet alloy powder-Determination of iron contentSubject content and scope of application
This standard specifies the determination method of iron content in cobalt 1-5 type permanent magnet alloy powder, GB/T15679.2-1995bzxz.net
This standard is applicable to the determination of iron content in cobalt 1-5 type permanent magnet alloy powder, the determination range: 0.02%~0.50%. 2 Reference standards
GB1.4 Guidelines for standardization work Provisions for the preparation of chemical analysis methods GB1467 General principles and general provisions for chemical analysis methods of metallurgical products GB7728 General principles for flame atomic absorption spectrometry for chemical analysis of metallurgical products 3 Principle of the method
The sample is decomposed by hydrochloric acid, and the absorbance of iron is measured at a wavelength of 248.3nm by an atomic absorption spectrophotometer using an air-acetylene flame in a dilute hydrochloric acid medium. Calculate the iron content by the standard addition method. 4 Reagents
4.1 Hydrochloric acid (1+1).
4.2 Iron standard stock solution: Weigh 0.1000g iron (99.9%) in a 150mL beaker, add 30mL hydrochloric acid (1+5), heat at low temperature until completely dissolved, and cool to room temperature. Transfer to a 1000mL volumetric flask, dilute to scale with water, and mix. This solution contains 100pg iron in 1mL. 4.3 Iron standard solution: Transfer 20.00mL of iron standard stock solution (4.2) to a 100mL volumetric flask, dilute to scale with water, and mix. This solution contains 20 μg iron in 1mL.
5 Instrument
Source electron absorption spectrophotometer with iron hollow cathode lamp. Under the best working conditions of the instrument, any instrument that can meet the following indicators can be used. Sensitivity: In a solution that is consistent with the matrix of the sample solution being measured, the characteristic concentration of iron is not greater than 0.056 g/mL. Precision: When the absorbance is measured 10 times with the standard solution of the highest concentration, the standard deviation shall not exceed 1.0% of the average absorbance; when the absorbance is measured 10 times with the standard solution of the lowest concentration (not the zero standard solution), the standard deviation shall not exceed 0.5% of the average absorbance of the standard solution of the highest concentration.
Linearity of working curve: Divide the working curve into five sections according to the concentration, and the ratio of the absorbance difference of the highest section to the absorbance difference of the lowest section shall not be less than 0.7.
See Appendix A (reference) for instrument working conditions. Approved by the State Administration of Technical Supervision on August 11, 1995 and implemented on April 1, 1996
6 Analysis steps
6.1 Determination quantity
GB/T 15679.2—1995
Weigh two samples for parallel determination and take the average value. 6.2 Samples
Weigh the samples according to Table 1, accurate to 0.0001g. Table 1
Iron content, %
0. 02 --0. 06
>0. 06~0. 20
≥0.20~0. 50
6.3 Blank test
Carry out a blank test with the sample.
6.4 Determination
Sample, g
Dissolve the sample and add hydrochloric acid (4.1) volume, ml) 8
6.4.1 Place the sample (6.2) in a 100mL beaker, add hydrochloric acid (4.1) according to Table 1 and heat until it is completely dissolved, evaporate the solution to 2~～3mL, and cool to room temperature.
6.4.2 Transfer the solution (6.4.1) into a 50mL volumetric flask, dilute with water to the mark, and mix. 6.4.3 Transfer 5 portions of 2.00mL of the test solution (6.4.2) into a group of 10mL volumetric flasks, add 0, 1.00, 1.50, 2.00, 4.00mL of the iron standard solution (4.3) respectively, dilute with water to the mark, and mix. 6.4.4 Using an air-acetylene flame, measure the absorbance of the test solution (6.4.3) at a wavelength of 248.3 nm using water as the zero setting on an atomic absorption spectrophotometer. Draw a standard addition curve with the iron concentration as the abscissa and the absorbance as the ordinate. Use the extrapolation method to find the iron concentration of the test solution from the standard addition curve.
Calculation and expression of analysis results
Calculate the percentage of iron in the cobalt permanent magnet alloy powder according to the following formula: Fe(%) - (c-co). VV, X 10-s× 100
Wherein: c-iron concentration of the test solution obtained from the standard addition curve, μg/mL; cCo-iron concentration of the blank test solution obtained from the standard addition curve, μg/mL; Vtotal volume of the test solution, ml
Vi--volume of the test solution, mL,
Vavolume of the tested solution, mL,
m---mass of the sample, g.
8 Allowable difference
The difference in analysis results between laboratories should not be greater than the allowable difference listed in Table 2. 242
Iron content
0.020~0.060
>0. 060~~0. 200
>0.2000.500
GB/T 15679. 2--1995
Tolerance
Instrument model
WFX-1D
Additional instructions:
GB/T15679.2—-1995
Appendix A
Instrument working conditions
(reference)
This standard was proposed by the Rare Earth Office of the State Planning Commission. Spectral passband
This standard was drafted by Shanghai Yuelong Nonferrous Metals Co., Ltd. This standard was drafted by Beijing General Research Institute of Nonferrous Metals. The main drafters of this standard are Zhen Rongqiao and Yuan Genle. 244
Burner height
Air flow
Acetylene flow
Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.